The present invention relates to a disk cartridge storage and retrieval apparatus for storing a multitude of disk cartridges each containing therein a disk as an information recording medium into a stocker, and retrieving a desired one of the cartridges from the stocker, loading it into an information recording and reproducing device, and returning, after reproduction of the information recorded on the disk contained therein or recordation onto the disk of pieces of information, it to a predetermined original location in the stocker.
conventionally, an example of such a disk cartridge storage and retrieval apparatus is known from Japanese Patent Laid-Open No. 61-258366. As perspectively illustrated in FIG. 7, the apparatus disclosed therein includes a box-shaped housing 101 in which a stocker 103 is installed for storing a multitude of disk cartridges 102 (hereinafter simply referred to as cartridges) each containing therein an information recording disk such as an optical disk, a magnetic disk, etc., in a horizontal attitude and in a vertically spaced parallel relation with respect to each other. Inside the housing 101 under the stocker 103, two information recording and reproducing devices 104, 104 for recording and reproducing information onto and from the disk in a cartridge 102 are horizontally disposed in a vertically spaced parallel relation with each other. Also, within the housing 101, there is disposed a carrier mechanism 105 which operates to selectively take out one of the cartridges 102 from the stocker 103, load it into one of the recording and reproducing devices 104, 104 and returns it to an original storage location in the stocker 103.
The carrier mechanism 105 includes a cartridge loading and unloading mechanism 106 for inserting and removing a cartridge 102 into or out of the recording and reproducing devices 104, a slide base 107 movable in the vertical direction while carrying the cartridge loading and unloading mechanism 106, and a drive mechanism 108 for vertically driving the slide base 107 to a level at which a desired one of the cartridges 102 is located in the stocker 103, and to another level at which an inlet opening of a desired one of the recording and reproducing devices 104, 104. The drive mechanism 108 comprises a pair of guide rails 109, 109 which are installed in the vertical direction in the housing 101 with their upper and lower ends fixedly secured to the top and the bottom of the housing 101, respectively, for guiding the vertical movement of the slide base 107, a pair of transmission belts 110, 110 connected with the slide base 107 and entrained around two pair of driven and drive pulleys (not shown) mounted on the top and bottom of the housing 101, and a motor 113 operatively connected with the drive pulleys for drivingly rotate them. Though not shown, the drive pulleys are mounted on the opposite ends of the rotating shaft of the motor 113, and the pulley shaft of each driven pulley is rotatably supported at its opposite ends by a pair of bearings each of which is mounted on the top plate 101a of the housing 101 with a shim being interposed therebetween for adjusting the vertical distance or clearance between the top plate 101a and the associated bearing. A rectangular-shaped balance weight 111 is secured to the transmission belt 110 at a location opposite to the slide base 107 with respect to the driven pulley. The balance weight 111 is vertically movable along a pair of vertically extending guide plates 112, 112, and it is supported on the opposite sides thereof by the guide plates 112, 112 through bearings such as linear bearings (not shown) so as to prevent any lateral swing or fluctuations thereof during its vertical movement. The guide rails 109, 109 for guiding the vertical motion of the slide base 107 are rigidly secured at an upper end and a lower end thereof to the top plate 101a and the bottom base 101b, respectively.
The apparatus further includes, though not shown in the drawings, a cartridge supply and discharge mechanism for supplying a cartridge 102 from the exterior to the apparatus and discharging it therefrom, and a control means for controlling the overall operation of the apparatus.
The operation of the above-described embodiment will now be described in detail. First, it should be noted that it is the basic operation of the apparatus to selectively take a desired cartridge 102 out of the stocker 103 and return a cartridge 102 once taken out to its original position in the stocker 103. For example, the operation of the apparatus of loading a cartridge 102 into one of the recording/reproducing devices 104, 104 will be described first.
When an operator sends to the unillustrated control means a command for taking an appropriate cartridge 102 out of the stocker 103 and load it into one of the recording/reproducing devices 104, the control means operates to start the motor 113 through the intermediary of an unillustrated controller for vertically moving the slide base 107. Thus, the cartridge loading and unloading mechanism 106 is driven by the motor 113 to upwardly move to a position in which the cartridge insertion opening 106a in the cartridge loading and unloading mechanism 106 is placed in confrontation with a desired one of the cartridges 102 stored in the stocker 103. Subsequently, when the slide base 107 has been moved to the desired position in this manner, the motor 113 is stopped by the control means. In this state, the cartridge loading and unloading mechanism 106 is first driven to horizontally move forwards or in its extending direction so as to grasp the desired cartridge 102 in the stocker 103, and then move back in a retracting direction so that the cartridge 102 is thereby taken out of the stocker 103. Once the cartridge 102 has fully come out of the stocker 103, the motor 113 is again energized to move, through the transmission belts 110, 110, the slide base 107 in the downward direction along the guide rails 109, 109 to a position confronting the inlet opening 104a in the one of the recording/reproducing devices 104, 104. At this time, the cartridge loading and unloading mechanism 106 may be caused to rotate a half revolution around the support shaft with respect to the slide base 107 so that it is turned upside down. Thereafter, the cartridge loading and unloading mechanism 106 is driven to extend toward the inlet opening 104a of the one recording/reproducing device 104 so as to insert the cartridge 102 thereinto, and after the cartridge 102 has been fully inserted into the inlet opening 104a, it is released from the cartridge loading and unloading mechanism 106, which is then retracted to a predetermined position. Likewise, in order to take a cartridge 102 out of one of the recording/reproducing devices 104, 104 and return it to the predetermined original position in the stocker 103, the above-described operations are performed in the reverse sequence.
With the above-described known disk cartridge storage and retrieval apparatus, the guide rails 109, 109 for guiding the vertical motion of the slide base 107 are rigidly secured at the upper and lower ends thereof to the top plate 101a and the bottom base 101b, respectively, of the housing 101 so that vibrations of the motor 113, which is installed on the bottom base 101b and generates relatively great power, occurring upon its starting as well as during the operation thereof, are liable to be directly transmitted from the bottom base 101b to the guide rails 109, 109, and thence to the slide base 107 and the cartridge loading and unloading mechanism 106 which are supported on the guide rails 109, 109, thus adversely affecting the accurate operations thereof and causing, in an extreme case, malfunctions and damage thereof.
Further, since the pulley shaft of the driven pulley is directly supported by a pair of bearings which are fixedly mounted on the top plate 101a of the housing 101, adjustment of the tension of the transmission belts 110, 110 is performed by changing the thickness of a shim disposed between each of the bearings and the top plate 101a, e.g., by replacing a shim with another appropriate one having a different thickness. As a result, the tension adjustment is time consuming and inefficient.
Moreover, since the balance weight 111 is supported at its opposite sides by the pair of guide plates 112, 112 through bearings such as linear bearings, which are relatively expensive, so as to be guided in its vertical movement, the cost of manufacture of the entire apparatus becomes high due in part to the use of the relatively expensive bearings.